How to sign a PDF online
- Drop your PDF on the page, or click Choose PDF or Try a sample PDF.
- Click Signature, then Draw it, Type your name in one of six script styles, or Upload a photo of it. Draw and Type offer Black or Dark blue ink. Click Use signature. Initials work the same way.
- Click the page where it belongs, drag to move it, and drag the blue corner square to resize it. Arrow keys, plus, minus and Delete work too.
- Add a Date (MM/DD/YYYY, DD/MM/YYYY or Month D, YYYY), Text, or a Check mark. Copy to all pages repeats the selected item on every page.
- Click Download signed PDF. Your original is not changed; the copy is named your-file-signed.pdf.
Electronic signature or digital signature
An electronic signature is any mark showing intent to sign, such as a drawn or typed name. A digital signature is a certificate-based seal that identifies the signer. This tool makes the first kind only.
The legal basics in the United States
The ESIGN Act and UETA give an electronic signature the same legal effect as ink for most contracts, if both sides agreed to sign electronically. Exceptions in 15 U.S.C. 7003 include wills, family law papers, court orders and some notices. This is general information, not legal advice.
How your signature is saved
pdf.js draws the page. On download, pdf-lib adds signatures as images, checkmarks as lines, and dates and text as Helvetica text. Positions follow the PDF's own coordinates, so rotated pages stay upright. Text Helvetica cannot show, such as Chinese, becomes a picture.
Worked example
Click Try a sample PDF (sample-agreement.pdf, 1.4 KB, 1 page, 8.5 x 11 in). Click Signature, open the Type tab, enter Jane Q. Public, keep Dancing Script and Black ink, click Use signature, then click above the middle of the Client signature line. Click Date, then click above the Date line: it shows today's date as MM/DD/YYYY, for example 10/11/2026. Click Download signed PDF. The tool reports Saved sample-agreement-signed.pdf (about 11 to 14 KB, depending on browser) with 2 items on 1 page.
Tips for a clean signature
A signature 1.5 to 2.5 inches wide looks natural; the default is about 150 points, or up to 260 for a long name. For an uploaded photo, use even light, white paper and a dark pen. Dark blue ink helps a signed copy stand out from a photocopy. Make a PDF from a photo of a form with image to PDF, join pages with the PDF merger, and shrink the result with the PDF compressor.
Limits and edge cases
- A PDF with a certificate-based digital signature shows it as broken after any change, because the file is rewritten. Sign a copy.
- Existing form fields are kept. A field with a solid background would cover an item placed on it, so the tool ticks Flatten form fields for you when an item lands on one.
- Files up to about 150 MB open.
Sign PDF FAQ
Is a signature added with this tool legally binding?
In the United States, usually yes. The ESIGN Act and UETA give electronic signatures the same legal effect as ink for most contracts. Wills, family court papers and court orders are common exceptions.
Is my PDF uploaded anywhere?
No. The PDF is opened and saved inside your browser tab and never sent to a server. Only the code libraries download, once (about 1 MB).
Can I sign a PDF on my iPhone or Android phone?
Yes. Open this page in Safari or Chrome, pick the PDF from Files or Downloads, tap Signature, draw with your finger, tap Use signature, tap the page to place it, then tap Download signed PDF.
Why can't I sign my password-protected PDF?
A signed copy means rewriting the file, and this tool cannot do that while the file is encrypted. Remove the password first with the PDF password remover (you need the password), then sign the unlocked copy.
Does the signed PDF have a watermark?
No. The only changes are the items you place. There is no watermark, no sign-up and no limit on pages.
Sources: ESIGN Act, 15 U.S.C. 7001; 15 U.S.C. 7003, exceptions; Uniform Law Commission, UETA.